Weeks & calendars

What Week Is It? Today Is Week 43

Today: Saturday, October 24, 2026 · Eastern Time (America/New_York)

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ISO week 43 of 2026

Week 43 runs from Monday, October 19, 2026 through Sunday, October 25, 2026.

Dates use Eastern Time (America/New_York). Remaining-year counts exclude the reference date and include December 31. Weeks remaining are full seven-day blocks, with remaining days shown separately.
ISO weeks start Monday. Week 1 contains January 4. The ISO week-year can differ from the calendar year. Not every ISO year has Week 53.
Gregorian leap years are divisible by 4, except century years unless divisible by 400.

Shows the ISO 8601 week number for any date, or the Monday-to-Sunday dates of any week number in a given year.

January 1, 2027 is in week 53 of 2026. Week 1 of 2027 starts on Monday, January 4, 2027.

When does week 1 start?: Week 1 is the week, starting on Monday, that contains the year's first Thursday. So January 1 can belong to the last week of the previous year.
How many weeks are in a year?: Most years have 52 ISO weeks. A year has 53 when it starts on a Thursday, or when it is a leap year that starts on a Wednesday.